1. Field of the Invention
The present invention relates to a method and system for controlling operation of a hand-held portable cellular telephone, and more particularly to a method for controlling a switchover of an operation mode of an integrally combined television (TV) and portable cellular phone (hereinafter, referred to as xe2x80x9cTV phonexe2x80x9d).
2. Description of the Related Art
In recent years, rapid and wide spread use of portable cellular telephones as a personal communication appliance has driven development of portable phones with a variety of functions in addition to a simple conversation function. For example, portable phones have developed to include a calculator, a biorhythm checking feature, and the capability of transmitting and/or receiving images of a TV and a video camera. The term xe2x80x9cTV phonexe2x80x9d herein refers to wireless portable cellular phones of all types which also provide television (TV) broadcast through a display unit of the portable phone, in addition to a cordless telephone conversation feature for telecommunication.
An example of the above TV phone is disclosed in Korean Patent Application No. 1995-46026 entitled xe2x80x9cA Combined TV Receiver and Cellular Phonexe2x80x9d by LG Electronics Co., Ltd., filed in the Korean Industrial Property Office on Dec. 1, 1995 and published on Jul. 31, 1997 by that Office.
For reception of a TV broadcast, the portable phone is equipped with two radio frequency units therein, as disclosed in the above-mentioned Korean patent application 1995-46026. The reason for this is that a frequency bandwidth necessary for transmitting and receiving telecommunication messages (i.e., voice and data) is different from that for a TV broadcast. An operation mode of the TV phone is classified into a phone mode, a waiting mode, and a TV mode, which is also used as the waiting mode. When operating in the TV mode, the TV phone allows a user to watch and hear images and voices of the television program received on a display unit, i.e. a Thin Film Transistor (TFT) Liquid Crystal Display (LCD), and a speaker or an earphone of the portable phone.
Disadvantages arise in the prior art when the TV phone is operating in the TV mode and there is an incoming call and/or an incoming character data message.
There is a need for a portable TV phone that allows the operation mode of the TV phone to be automatically switched from a TV mode to a phone mode so that the user (i.e., the called party) can speak over the telephone with the calling party and the circuitry associated with the TV function can be disabled in order to prevent unnecessary consumption of the battery during the ensuing phone conversation. In addition, there is a need for a portable TV phone that allows the user to reject the incoming call in order to continue to view the TV program when the user does not care to respond to the incoming call.
The TV phone of the above-cited patent application 1995-46026 cannot process character messages received by the transmitter/receiver of the telecommunications feature when the TV is operating in TV mode and receiving a TV signal via the receiver of the TV. In addition, when the TV phone of patent application 1995-46026 receives an incoming voice call, the telephone rings, but it is impossible to directly switch the TV mode to the phone mode while in the TV mode. Accordingly, the user must turn off the TV phone, manually switch the TV mode to the phone mode with regard to every incoming call, and turn the phone back on. This consumes battery power and is highly inconvenient to the user.
Therefore, an object of the invention is to provide a method for controlling switching of an operation mode of a TV phone where the operation mode of the TV phone is automatically switched from a TV mode to a phone mode upon the occurrence of an incoming of a call.
It is another object of the invention to provide a method for controlling a switching of an operation mode of a TV phone where the user is informed of the call. It is also an objective that, upon reception of a call, the user may choose whether to switch the TV phone from the TV mode to the phone mode.
In accordance with one embodiment of the present invention, these objectives are accomplished by providing a method for controlling an operation mode switching of a portable TV phone. The TV phone includes a TV unit that reproduces and outputs a video signal from a selected channel. A TV audio signal processor processes an audio signal received by the TV unit for the selected channel and outputs it as audible sound. As described below, a display unit receives the video signal from the TV unit and displays the inputted video signal from the selected channel while in the TV mode. A mobile radio frequency processor (xe2x80x9cMRFUxe2x80x9d) receives data of a forward channel transmitted from a base station. A mobile signal processor (MSP) has a TV mode and a phone mode, provides a channel selection signal to the TV unit in the TV mode and generates a character control signal in response to an incoming call. An on-screen display (xe2x80x9cOSDxe2x80x9d) generates character images (including image character and graphic images) corresponding to the character control signal received at an input of the OSD. A multiplexer receives as input the character images of the OSD and the video signal of the TV unit and has an output that interfaces with the display unit. The multiplexer outputs the character images of the OSD or the video signal of the TV unit to the display unit based on a control signal received by the multiplexer from the MSP.
The method includes the steps of alerting the user of an incoming call by display of a character message on the display unit and/or an audio signal outputted from a speaker of the TV phone. The alert is in response to an incoming call signal transmitted from the base state when the TV phone is in the TV mode, i.e., in a state in which the video signals of the selected channel from the TV unit are displayed on the display unit and the audio signal for the selected channel are output by the TV audio signal processor. The TV phone is switched from the TV mode to the phone mode by disabling the operation of the TV unit in response to input by the user of a command that permits the call to proceed. The command initiates transmission of an incoming call response message to the calling party through a reverse channel. (Alternatively, the switching and proceeding with the call can occur automatically, if an appropriate setting is made by the user.) However, the TV phone is maintained in TV mode and the character message and/or audio signal used to alert the user to an incoming call is terminated in response to input by the user of a command rejecting the incoming of the call from the calling party.